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Technical efficiency of hybrid maize growers: A stochastic frontier model approach 预览
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作者 Imad Ali HUO Xue-xi +3 位作者 Imran Khan Hashmat Ali Khan Baz Sufyan Ullah Khan 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第10期2408-2421,共14页
This study investigated the effect of credit constraints and credit unconstraints on the technical efficiency of hybrid maize growers in the Khyber Pakhtunkhwa Provinee (KPK) of Pakistan. The primary data were collect... This study investigated the effect of credit constraints and credit unconstraints on the technical efficiency of hybrid maize growers in the Khyber Pakhtunkhwa Provinee (KPK) of Pakistan. The primary data were collected by a direct elicitation method from 510 maize growers of KPK Provinee. Stochastic frontier model techniques were used for technical efficiency analyses. The results revealed that the mean technical efficiency differenee between the two groups was 10.2%. The results of tech nical in efficie ncy effect modeling dem on strated that education of the household head, family size, number of married family members, off-farm income, farming experienee, tractor drill, water irrigation through a lined course, certified seed, extension services, household saving variables, and a credit size variable had positive effects on technical efficiency for both credit constrained farmers (CCFs) and credit unconstrained farmers (UCCFs). In addition, age of household head and fragmented land values had negative effects on technical efficiency for both groups. However, the interest rate had positive and negative impacts on the technical efficiency of CCFs and UCCFs, respectively. Our results have significant implicatio ns for policies related to land use, interest rate, and banking sector expansion in the rural areas of Pakistan. 展开更多
关键词 stochastic FRONTIER analysis MAIZE GROWERS technical efficiency CREDIT RATIONING and CREDIT MARKETS in Pakistan
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The deubiquitinating gene Usp29 is dispensable for fertility in male mice
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作者 Zhu Huang Manan Khan +6 位作者 Jianze Xu Teka Khan Hui Ma Ranjha Khan Hafiz Muhammad Jafar Hussain Xiaohua Jiang Qinghua Shi 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第4期544-552,共9页
The balanced actions between ubiquitination and deubiquitination precisely control the levels of various proteins vital for spermatogenesis.Ubiquitin-specific processing proteases(USPs)are the largest family of deubiq... The balanced actions between ubiquitination and deubiquitination precisely control the levels of various proteins vital for spermatogenesis.Ubiquitin-specific processing proteases(USPs)are the largest family of deubiquitinatingenzymes(DUBs),containing more than 50 members.So far,the functions of only a few USPs in male fertility have been studied,the roles of the majority are yet unknown.The present study aimed to explore the function of Usp29(ubiquitin-specific protease 29)in male fertility.We found that Usp29 showed predominant expression in mouse testis,and its m RNA expression started to increase at 14 days postpartum(dpp),with a peak at 28 and 35 dpp.Using CRISPR/Cas9 technology,we generated Usp29 knockout mice(Usp29–/–).Usp29–/–mice exhibited no overt developmental anomalies.Further examination revealed that Usp29–/–mice had normal fertility and showed no detectable difference in the testis/body weight ratio,testicular and epididymal histology as well as epididymal sperm count from the wild-type littermates.Moreover,Usp29 is not a pseudogene in mice.Taken together,our study first reported that though Usp29 is predominantly expressed in the testis,it is not essential for male fertility in mice. 展开更多
关键词 Usp29 MOUSE TESTIS FERTILITY
社会政治地理和生态压力对传统牧业制度的影响综述
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作者 MUHAMMAD Khurshid MOHAMMAD Nafees +3 位作者 ABDULLAH Khan MEHMET Somuncu ASHFAQ Ahmad Khan WAJID Rashid 《地理学报:英文版》 SCIE CSCD 2019年第10期1758-1770,共13页
Pastoralism is a viable socio-economic system-shaped by landless and agro-pastoral communities in many pastoral regions of the world. This system is mainly based on seasonal migration of pastoralists and their livesto... Pastoralism is a viable socio-economic system-shaped by landless and agro-pastoral communities in many pastoral regions of the world. This system is mainly based on seasonal migration of pastoralists and their livestock herds between upland and lowland pastures. Traditionally pastoral activities make significant contributions to mountain livelihood subsistence, regional economies and environmental sustainability. However, the pastoralist’s lifestyle and their economies are increasingly confronted to various socio-political, economic and ecological stresses from the last few decades. Extensive literature reviewed on this subject with the aim to explore the current emerging challenges faced by pastoral communities in different pastoral regions. It has been revealed from literature that the prevalent socio-political and economic stress on pastoralism caused by modernization, insecure land tenure, integration of market economy, civil insecurities and pastoralist’s exclusion in states policies while ecological stress on pastoral activities emerged with increasing focus on nature conservation in pastoral regions and climate change induced hazards and disasters. As a consequence of these challenges, pastoral households are abandoning livestock herding–as a traditional way of life and are in continuous transition to transform their pastoral practices and institutions. Thus, the attention and consultation of key stakeholders are needed toward pastoral resource development that improve and sustain traditional pastoral practices in a socio-politically and ecologically stressed environment of the world. 展开更多
关键词 pastoralism MARGINALIZATION PASTORAL system PASTURES livestock PASTORALISTS
Effects of bismuth on structural and dielectric properties of cobalt-cadmium spinel ferrites fabricated via micro-emulsion route
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作者 Furhaj Ahmed Sheikh Muhammad Khalid +6 位作者 Muhammad Shahzad Shifa H M Noor ul Huda Khan Asghar Sameen Aslam Ayesha Perveen Jalil ur Rehman Muhammad Azhar Khan Zaheer Abbas Gilani 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第8期408-416,共9页
Spinel ferrites have a significant role in high-tech applications.In the present work nano-crystalline ferrites having general formula Co0.5Cd0.5BixFe2-xO4 with(x=0.0,0.05,0.1,0.15,0.2,and 0.25)are synthesized via mic... Spinel ferrites have a significant role in high-tech applications.In the present work nano-crystalline ferrites having general formula Co0.5Cd0.5BixFe2-xO4 with(x=0.0,0.05,0.1,0.15,0.2,and 0.25)are synthesized via micro-emulsion route.Powder x-ray diffraction(XRD)studies discover the FCC spinel structure.Crystalline size is calculated in a range of 11 nm-15 nm.Lattice parameter calculations are reduced due to its substitution which leads to the exchange of large ionic radius of Fe^3+for small ionic radius of Bi^3+.The x-ray density is analyzed to increase with doping.Fourier transform infrared spectroscopy(FTIR)is performed to analyze absorption band spectra.The two absorption bands are observed in a range of 400 cm^-1-600 cm^-1,and they are the characteristic feature of spinel structure.Thermo-gravimetric analysis(TGA)reveals the total weight loss of nearly 1.98%.Dielectric analysis is carried out by impedance analyzer in a frequency span from 1 MHz to 3 GHz by using the Maxwell Wagner model.Dielectric studies reveal the decrease of dielectric parameters.The alternating current(AC)conductivity exhibits a plane behavior in a low frequency range and it increases with the applied frequency increasing.This is attributed to the grain effects in a high frequency range or may be due to the reduction of porosity.Real and imaginary part of impedance show the decreasing trend which corresponds to the grain boundary action.The imaginary modulus shows the occurrence of peak that helps to understand the interfacial polarization.Cole-Cole graph shows a single semicircle which confirms that the conduction mechanism is due to the grain boundaries at low frequency.Dielectric studies reveal the applicability of these ferrites in high frequency equipment,microwave applications,high storage media,and semiconductor devices. 展开更多
关键词 CO-FERRITE NANOCRYSTALLINE ferrites XRD MICROEMULSION DIELECTRIC properties
Quality and Crop Yield Potential of Moderately Degraded Alfisols Under Different Nutrient Inputs and Cropping Patterns
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作者 Wiqar AHMAD Farmanullah KHAN +1 位作者 Zahir SHAH Muhammad Jamal KHAN 《土壤圈:英文版》 SCIE CAS CSCD 2019年第2期235-247,共13页
Crop performance on degraded soil needs special management practices to overcome soil quality limitations. In a 2-year(from summer 2006 to winter 2007–2008) field trial on a moderately degraded Alfisol in Swabi Distr... Crop performance on degraded soil needs special management practices to overcome soil quality limitations. In a 2-year(from summer 2006 to winter 2007–2008) field trial on a moderately degraded Alfisol in Swabi District(34°7′12′′N, 72°28′20′′E), Pakistan,the effects of three cropping patterns, cereal-cereal(CC), cereal-legume(CL), and cereal-cereal and legume intercrop(CLI), were tested in main plots under four fertilization treatments in sub-plots, including no fertilization(control), farmers’ practice(FP, 60:45 kg ha-1 N:P2O5), recommended dose(RD, 120:90:60 kg ha-1 N:P2O5:K2O), and integrated nutrient management(INM, 20 t ha-1 farmyard manure integrated with 50% N, 100% P, and K of recommended dose), using a split-plot randomized complete block design. The performance of CL was superior than CC in plant height, leaf area index(LAI), cob length, grain yield, biological yield, and grain protein(8%, 26%, 8%, 5%, 10%, and 8% increases, respectively), while CLI confirmed significant improvement only in LAI(25%) over CC. Response to nutrient inputs from all sources was in the order of INM > RD > FP > control, and the maximum net economic return by INM(23% and 2.5 times higher than RD and FP, respectively) indicated severe deficiency of both macro-and micro-nutrients in the soil as well as degraded physical properties. Increases in soil organic matter, total N, total mineral N, available P and K, total porosity, and available water-holding capacity by 6%, 34%, 24%, 50%, 13%, 5%, and 7%, respectively, and decrease in soil bulk density by 4% after four crop seasons indicated optimistic changes in soil quality as a result of the combined effects of fertilization from organic and inorganic sources and legumes within crop rotation. This study suggests that keeping the soil covered under cereal-legume rotation crops all year round and treatment with INM(50% N from organic source and 50% from inorganic source) are the best management practice for sustained production on degraded Alfisols. 展开更多
关键词 CROP rotation CROP performance degraded soil farmyard MANURE integrated nutrient management LEGUME INTERCROP sustained production
Effectiveness of radiative heat flux in MHD flow of Jeffrey-nanofluid subject to Brownian and thermophoresis diffusions 预览
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作者 Muhammad Ijaz Khan Tasawar Hayat +2 位作者 Muhammad Waqas Ahmed Alsaedi Muhammad Imran Khan 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第2期421-427,共7页
Our interest here in this investigation is to explore the thermophoresis and Brownian motion characteristics in flow induced by stretched surface.Electrically conducted Jeffrey material formulates the flow equation.Li... Our interest here in this investigation is to explore the thermophoresis and Brownian motion characteristics in flow induced by stretched surface.Electrically conducted Jeffrey material formulates the flow equation.Linear forms of stretching and free stream velocities are imposed.Nonlinear radiation and convective heating processes describe the phenomenon of heat transfer.Passive controls of nanoparticles are considered on the boundary.The compatible transformations produce the strong nonlinear differential systems.The problems are computed analytically utilizing HAM.Converge nee domain is detennined and major results are concluded for different parameters involved.Heat transfer rate and drag force are also explained for various physical variables.Our analysis reveals that heat transfer rate augments via larger radiation parameter and Biot number.Moreover larger Brownian motion and thermophoresis parameters have opposite characteristics on concentration field. 展开更多
关键词 Jeffrey NANOMATERIAL non-linear RADIATIVE heat flux convective boundary conditions.Brownian and THERMOPHORESIS DIFFUSIONS
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Surveillance of Chikungunya virus activity in some North-eastern states of India
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作者 Prafulla Dutta Siraj A.Khan +5 位作者 Anil C.Phukan Sarat Hazarika Naba K.Hazarika Sumi Chetry Abdul M.Khan Harpreet Kaur 《亚太热带医药杂志:英文版》 SCIE CAS 2019年第1期19-25,共7页
Objective: To detect the prevalence pattern of Chikungunya virus in three states of Northeast India. Methods: A total of 1 510 samples were collected from different private and government hospitals of Assam, Arunachal... Objective: To detect the prevalence pattern of Chikungunya virus in three states of Northeast India. Methods: A total of 1 510 samples were collected from different private and government hospitals of Assam, Arunachal Pradesh and Meghalaya. Serum was tested for the presence of IgM antibodies against Chikungunya virus followed by RT-PCR for amplification of Chikungunya E1 gene region using specific primers. Results: Overall, 11.83%(172/1 454) clinical samples were positive by MAC-ELISA and/or RT-PCR assay. Asymptomatic infection was seen in 17.86%. Males were more affected than females and age group 16-30 years was mostly affected. Fever(100.00%) was the primary symptom followed by headache(72.03%) and arthralgia(41.53%). Only 118 Chikungunya positive cases could be traced, of which 25.42% complained about sequelae of infection. In entomological investigation, Aedes aegypti was more predominant(92.10%) than Aedes albopictus(7.90%). No mosquito pools could be incriminated for Chikungunya virus. Conclusions: In this study, Chikungunya was observed to be prevalent in Assam, Arunachal Pradesh and Meghalaya. Though Chikungunya is a selflimiting infection, increasing morbidity by CHIKV infection is affecting social and economic status of individual. Thus, a community empowerment to effectively control mosquito population by employing different mosquito control measures along with personal protection is mandatory to tackle future outbreak of the disease. 展开更多
关键词 CHIKUNGUNYA NORTHEAST INDIA AEDES aegypti AEDES ALBOPICTUS
Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
General Solution for Unsteady Natural Convection Flow with Heat and Mass in the Presence of Wall Slip and Ramped Wall Temperature
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作者 Saeed Ullah Jan Sami Ul Haq +2 位作者 Syed Inayat Ali Shah Ilyas Khan Muhammad Atif Khan 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第6期647-657,共11页
This work is focused on the effect of heat and mass transfer with unsteady natural convection flow of viscous fluid along with ramped wall temperature under the assumption of the slip wall condition at the boundary. A... This work is focused on the effect of heat and mass transfer with unsteady natural convection flow of viscous fluid along with ramped wall temperature under the assumption of the slip wall condition at the boundary. Analytical solutions are obtained by using Laplace transformation to the non-dimensional set of governing equations containing velocity, temperature and concentration. Moreover, the expression for skin-friction is derived by differentiating the analytical solutions of fluid velocity. Numerical tables for Skin-friction, Sherwood number and Nusselt-number are examined. For the physical aspects of the flow, we use various values of involved physical parameters such as Prandtl number(Pr), slip parameter(η), Schmidt number(Sc), buoyancy ratio parameter(N), Sherwood number(Sh), and time(t). Additionally, the general solutions are plotted graphically and a comprehensive theoretical section of numerical discussions is included. 展开更多
关键词 SLIP BOUNDARY condition HEAT and MASS transfer skin-friction
Mechanical, thermal and interfacial properties of Carbon-Kevlar reinforced epoxy composite 预览
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作者 Milon Hossain Kamrun N. Keya +6 位作者 Nasrin A. Kona Naimul Islam Farjana A. Koly Mubarak A. Khan Abu Bakar Siddiquee Jumana Mahmud Ruhul A. Khan 《材料工程研究(英文)》 2019年第2期56-63,共8页
Twill woven Carbon-Kevlar (CK) fabric was reinforced in epoxy matrix by conventional hand lay-up process. The fabric weight fraction in the composites was kept around 58% and stacking sequence was varied from single t... Twill woven Carbon-Kevlar (CK) fabric was reinforced in epoxy matrix by conventional hand lay-up process. The fabric weight fraction in the composites was kept around 58% and stacking sequence was varied from single to five plies. Tensile test was performed and the fracture surface after tensile test was evaluated by scanning electron microscope (SEM). The test result revealed that the tensile properties are strongly dependent on the number of plies. Three point flexural test of the composite was also carried and an increasing trend was observed. Maximum impact energy was recorded for CK3 sample by 202.7 KJ/m2. Thermal stability of the composite was studied via the thermo gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR) result show interaction between fiber and matrix material. Finally, CK fabric reinforced epoxy-based composites showed balanced and tailor-able mechanical properties by varying the number of plies, suitable for desired applications in many areas including building, construction, marine, automotive etc. 展开更多
关键词 Carbon-Kevlar fabric epoxy polymer composites MECHANICAL PROPERTIES THERMAL PROPERTIES
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MWCNTs/SWCNTs Nanofluid Thin Film Flow over a Nonlinear Extending Disc: OHAM Solution
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作者 GOHAR TAZA Gul +3 位作者 WARIS Khan MUHAMMAD Shuaib MUHAMMAD Altaf Khan EBENEZER Bonyah 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第1期115-122,共8页
The aim of this research is the improvement towards the consumption of energy in the field of engineering and industry.The efforts have been paid to the enhancement of heat transmission and cooling process through a n... The aim of this research is the improvement towards the consumption of energy in the field of engineering and industry.The efforts have been paid to the enhancement of heat transmission and cooling process through a nanofluid coating of a nonlinear stretching disc.The combination of Water (H2O)and multiple walled carbon nanotubes (MWCNT)/single walled carbon nanotubes (SWCNT)have been used as a nanofluid.The spreading of a thin nano-layer with variable thickness over a nonlinear and radially stretching surface has been considered.The estimated results of the problem have been accomplished using the Optimal Homotopy Analysis Method (OHAM).The residual errors of the OHAM method have been shown physically and numerically.The important physical parameters of skin friction and Nusselt number have been calculated and discussed.The other embedding parameters like generalized magnetic parameter,Prantl number,nanofluid volume fraction and Eckert number have been intended and discussed. The obtained results have been compared with the Numerical (ND-Solve)method for both sorts of CNTs.The closed agreement of both methods has been achieved. 展开更多
关键词 CNTs-H2O based NANOFLUID variable thin layer NONLINEAR radially STRETCHING DISC magnetic field skin friction and Nusselt number OHAM & numerical method
Effect of Marsdenia tenacissima extract on G2/M cell cycle arrest by upregulating 14-3-3σ and downregulating c-myc in vitro and in vivo
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作者 Li Sun Qurat UI Ain +3 位作者 Ying-sheng Gao Ghulam Jilany Khan Sheng-tao Yuan Debmalya Roy 《中草药:英文版》 CAS 2019年第2期169-176,共8页
Objective: Marsdenia tenacissima extract(MTE) is a traditional Chinese herbal medicine with anti-cancer activity. In some previous studies, different mechanism actions of the anti-cancer effect of MTE have been reveal... Objective: Marsdenia tenacissima extract(MTE) is a traditional Chinese herbal medicine with anti-cancer activity. In some previous studies, different mechanism actions of the anti-cancer effect of MTE have been revealed. In this study, we first observed that MTE exhibited G2/M cell cycle arrest on two different human breast cancer cell lines, MDA-MB-231 and MCF-7 by mediating 14-3-3σ and c-myc.Methods: The effect of MTE on G2/M cell cycle arrest was evaluated in MDA-MB-231 and MCF-7 cell lines. MTT assay was done for evaluation of cell viability. Flow cytometry was employed for cell cycle analysis. Western blotting analysis and immunohistochemistry were performed to analyze the expression of G2/M cell cycle-related key protein in cells and tissue samples. Animal studies have been conducted to elucidate the anti-tumor effect of MTE.Results: Cell cycle is the backbone for developing cancer. Cell cycle proteins play a major role in the progression of cell cycle and cell proliferation. However, some key protein directly or indirectly modulate the action of cell cycle protein that highly affect cell cycle regulation. In order to investigate cellular proliferation of cancer, we observed that MTE induced the upregulation of 14-3-3σ and downregulation of c-myc,and then reduced the expression of G2/M cell cycle associated key protein, leading to the inhibition of cellular entry into mitosis phase. We also confirmed that MTE exerted a significant antitumor effect on the MDA-MB-231 xenograft model in vivo.Conclusion: G2/M cell cycle arrest occurred by the action of MTE, mediated by the upregulation of 14-3-3σ as well as downregulation of c-myc in MDA-MB-231 and MCF-7 cell lines. 展开更多
关键词 C-MYC G2/M ARREST Marsdenia tenacissima EXTRACT MCF-7 MDA-MB-231 14-3-3σ
Thulium-Doped Fiber Amplifier for Blue Light Signal Amplification 预览
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作者 Muhammad Hanif Ahmed Khan Khushik Chun Jiang 《中国通信:英文版》 SCIE CSCD 2019年第5期181-188,共8页
Fluoride-based thulium-doped visible light fiber amplifier(TmVLFA), which can be used to amplify the blue light signal for a visible light communication(VLC) system,is theoretically demonstrated for the first time acc... Fluoride-based thulium-doped visible light fiber amplifier(TmVLFA), which can be used to amplify the blue light signal for a visible light communication(VLC) system,is theoretically demonstrated for the first time according to the best of our knowledge. The transition rate equations and power propagation equations are solved to predict the dependence of the gain and noise figure on fiber parameters. The numerical results show that with the pump wavelength 1150 nm and pump power 800 mW, 2.75 m long thulium-doped fiber can amplify blue light(480 nm) signal up to 33.3 dB, and the noise figure is in the range from 3.0 to 3.5 dB. The model and numerical results encourage the use of fiber amplifier in VLC system for blue light amplification to extend the range of VLC. 展开更多
关键词 Tm-doped VISIBLE LIGHT FIBER AMPLIFIER VISIBLE LIGHT communication FIBER AMPLIFIER GAIN noise FIGURE
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探测并量化牙菌斑的红色荧光成像技术:先导性研究 预览
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作者 Zhao Liu Juliana Gomez +1 位作者 Soniya Khan Debbie Peru and Roger Ellwooda 《口腔护理用品工业》 CAS 2019年第1期23-31,共9页
口腔细菌里的卟啉类化合物使牙菌斑具有红色荧光特性,这种特性使得在没有显色剂的情况下,依然可以看到、探测并对牙菌斑进行评分。本文进行了两项研究。第一项研究包括了24名健康参与者,这些参与者在24小时内被禁止进行口腔清洁,然后从... 口腔细菌里的卟啉类化合物使牙菌斑具有红色荧光特性,这种特性使得在没有显色剂的情况下,依然可以看到、探测并对牙菌斑进行评分。本文进行了两项研究。第一项研究包括了24名健康参与者,这些参与者在24小时内被禁止进行口腔清洁,然后从这些参与者的牙齿表面收集牙菌斑,并制备成10%的溶液。用分光光度计扫描牙菌斑溶液,确定最合适的激发和发射波长,建立起一种红色荧光成像系统。14个健康受试者完成了第二项研究。在一个清洗周期后(1周),参与者进行基线预防并在研究期间被禁止进行口腔清洁。采用荧光成像系统在基线、24小时、48小时对参与者进行实时监测。牙医在牙菌斑显色后形成的红色图像上对牙菌斑进行临床评估。从图像中提取三个描述值并采用RUSBoost分类器衍生的计算机荧光对其评分,进行交叉验证。牙菌斑的红色荧光水平在48小时的累积过程中不断增加。牙菌斑的发展程度同时由牙医评估和计算机分析,结果显示,其在牙齿和受试者水平上具有显著差异性(p <0. 05)。临床牙菌斑和红色荧光牙菌斑具有中度相关性(r1/40. 62牙医,r1/40. 55计算机)。当牙菌斑的显示阈值为2的时候,牙医评估结果(敏感度71. 1%,特异性67. 7%,准确度70. 2%)和计算机评估结果(敏感度68. 4%,特异性62. 9%,准确度67. 1%)的一致性是最好的。鉴于与临床诊断的相关性,红色荧光成像技术具有为口腔卫生提供一种客观和有前景的评估方法的潜力。 展开更多
关键词 牙菌斑 自体荧光成像 口腔卫生 RUSBoost 分类器 计算机分析
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Spanning Simplicial Complex of Wheel Graph Wn
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作者 A. Zahid M.U. Saleem +3 位作者 A. Kashif M. Khan M.A. Meraj R. Irfan 《代数集刊:英文版》 SCIE CSCD 2019年第2期309-320,共12页
In this paper, we explore the spanning simplicial complex of wheel graph Wn on vertex set [n]. Combinatorial properties of the spanning simplicial complex of wheel graph are discussed, which are then used to compute t... In this paper, we explore the spanning simplicial complex of wheel graph Wn on vertex set [n]. Combinatorial properties of the spanning simplicial complex of wheel graph are discussed, which are then used to compute the f-vector and Hilbert series of face ring k[Δs(Wn)] for the spanning simplicial complex Δs(Wn). Moreover, the associated primes of the facet ideal IF(Δs(Wn)) are also computed. 展开更多
关键词 simplicial COMPLEXES SPANNING trees SPANNING simplicial COMPLEXES f-vectors HILBERT series VERTEX COVERS
Hypoxia-inducible factor 2αis a negative regulator of osteoblastogenesis and bone mass accrual 预览
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作者 Christophe Merceron Kavitha Ranganathan +9 位作者 Elizabeth Wang Zachary Tata Shreya Makkapati Mohd Parvez Khan Laura Mangiavini Angela Qing Yao Laura Castellini Benjamin Levi Amato J.Giaccia Ernestina Schipani 《骨研究:英文版》 SCIE CAS CSCD 2019年第1期91-104,共14页
Osteoblasts,which are the bone-forming cells,operate in a hypoxic environment.The transcription factors hypoxia-inducible factor-1α(HIF1)and HIF2 are key mediators of the cellular response to hypoxia.Both are express... Osteoblasts,which are the bone-forming cells,operate in a hypoxic environment.The transcription factors hypoxia-inducible factor-1α(HIF1)and HIF2 are key mediators of the cellular response to hypoxia.Both are expressed in osteoblasts.HIF1 is known to be a positive regulator of bone formation.Conversely,the role of HIF2 in the control osteoblast biology is still poorly understood.In this study,we used mouse genetics to demonstrate that HIF2 is an inhibitor of osteoblastogenesis and bone mass accrual.Moreover,we provided evidence that HIF2 impairs osteoblast differentiation at least in part,by upregulating the transcription factor Sox9.Our findings constitute a paradigm shift,as activation of the hypoxia-signaling pathway has traditionally been associated with increased bone formation through HIF1.Inhibiting HIF2 could thus represent a therapeutic approach for the treatment of the low bone mass observed in chronic diseases,osteoporosis,or aging. 展开更多
关键词 IS CELLS HAS
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Improved dielectric and electro-optical parameters of nematic liquid crystal doped with magnetic nanoparticles
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作者 Geeta Yadav Govind Pathak +4 位作者 Kaushlendra Agrahari Mahendra Kumar Mohd Sajid Khan V S Chandel Rajiv Manohar 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第3期223-229,共7页
This study investigates the effect of magnetic nanoparticles(NPs) on the weakly polar nematic liquid crystal(NLC).Different parameters of dielectric data were measured for both the homeotropic and planar aligned sampl... This study investigates the effect of magnetic nanoparticles(NPs) on the weakly polar nematic liquid crystal(NLC).Different parameters of dielectric data were measured for both the homeotropic and planar aligned samples as a function of frequency and temperature and the substantial changes have been noticed for the doped systems. Dielectric permittivity has been increased after the dispersion of magnetic NPs in the pure NLC. Dielectric anisotropy has also been influenced by incorporating the magnetic NPs with the NLC molecules. These results were attributed to the dipole–dipole interaction between the magnetic nanoparticles and nematic liquid crystal molecules. Electro-optical study indicated the faster rise time and fall time of the doped systems as compare to pure NLC. Threshold voltage has been calculated and found to be decreased for the doped systems. Moreover, we have also calculated the rotational viscosity and the splay elastic constant for pure and the doped systems. Both the rotational viscosity and splay elastic constant of the doped systems are found to be considerably lower than those of pure NLC. Change in these properties has been explained on the basis of molecular disturbances created by the interaction between the magnetic nanoparticle and LC director. This study reveals that the inclusion of magnetic NPs in weakly polar NLC can be useful to enhance the basic properties of the weakly polar NLC and make it a promising material for many display applications. 展开更多
关键词 magnetic nanoparticles DIELECTRIC PERMITTIVITY response time ROTATIONAL VISCOSITY
Properties of Chemically Synthesized Nano-geopolymer Cement based Self-Compacting Geopolymer Concrete(SCGC)
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作者 Muhammad Ali Sikandar Byung Wan Jo +1 位作者 Zafar Baloch Muhammad Asad Khan 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第1期98-106,共9页
The physical and mechanical properties of self-compacting geopolymer concrete(SCGC) using chemically synthesized nano-geopolymer cement was investigated. Nano-geopolymer cement was synthesized using nano-silica, alkal... The physical and mechanical properties of self-compacting geopolymer concrete(SCGC) using chemically synthesized nano-geopolymer cement was investigated. Nano-geopolymer cement was synthesized using nano-silica, alkali activator, and sodium aluminate in the laboratory. Subsequently, nine nanogeopolymer cement sbased SCGC mixes with varying nano-geopolymer cement content, alkali activator content, coarse aggregate(CA) content, and curing temperature were produced. The workability-related fresh properties were assessed through slump flow diameter and slump flow rate measurements. Mechanical performances were evaluated through compressive strength, splitting tensile strength, and modulus of elasticity measurements. In addition, rapid chloride penetration test, water absorption, and porosity tests were also performed. It was assessed that all mix design parameters influenced the fresh and hardened properties of SCGC mixes. Based on test results, it was deduced that nano-geopolymer cement SCGC performed fairly well. All the SCGC mixes achieved the 28-day compressive strength in the range of 60-80 MPa. Additionally, all mixes attained 60% of their 28-day strength during the first three days of elevated temperature curing. FTIR and SEM analyses were performed to evaluate the degree of polymerization and the microstructure respectively for SCGC mixes. 展开更多
关键词 GEOPOLYMER COMPRESSIVE strength SELF-COMPACTING concrete ALKALI ACTIVATOR NANO-SILICA
Ilizarov reconstruction of chronic bilateral calcaneovalgus deform让ies
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作者 Ming Chun Chan Suheal A. Khan 《中华创伤杂志:英文版》 CAS CSCD 2019年第4期202-206,共5页
Calcaneovalgus foot deformities are present in up to 35% of patients with lumbar spina bifida. Resultant heel weight bearing causes complications include those associated w让h pressure ulcers. Early surgical reconstru... Calcaneovalgus foot deformities are present in up to 35% of patients with lumbar spina bifida. Resultant heel weight bearing causes complications include those associated w让h pressure ulcers. Early surgical reconstruction is advocated to prevent deformity progression and rigidity. Several surgical techniques in paediatric populations have been described, but there remains a paucity of literature regarding reconstruction of chronic calcaneovalgus feet in adults. This case report describes our experience using the Ilizarov technique in the reconstruction of an adult presenting with chro nic calcaneovalgus feet. This is a 34-year-old lady with myelomeningocoele spina bifida of lumbar level 5 who presented with a history of multiple admissions for cellulitis and infections of bilateral heel pressure sores. Rigid calcaneovalgus deformities of both feet (45° on the right, 40° on the left) were noted on clinical examination and radiological investigations. Reconstruction with an Ilizarov frame allowed for gradual correction of both soft tissue and bone, correcting heel weight bearing ambulation, with the aim of preventing further complications from infected heel ulcers. While the correction of bony deformities is crucial, management of chronically contracted soft tissue must not be overlooked. An Ilizarov frame requires both an experienced surgeon and a motivated patient, but it allows for accurate reconstruction of bony deferm让ies, while allowing management of surrounding chronic soft tissue contractures with good functional outcome. 展开更多
关键词 ILIZAROV technique CALCANEUS Foot DEFORMITIES CONTRACTURE Meningomyelocele
Impact of bacterial chaperonin GroEL-GroES on bacteriorhodopsin folding and membrane integration
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作者 Xinwei Lu Baomei Xu +6 位作者 Haiyan Sun Junting Wei Haixia Chi Naseer Ullah Khan Xiaojuan Wang Xiaoqiang Wang Fang Huang 《生物物理学报:英文版》 CSCD 2019年第3期133-144,共12页
Our understanding of molecular chaperone function in membrane protein biogenesis lags far behind that in soluble protein biogenesis. Through a combined approach including isothermal titration calorimetry, UV-Vis spect... Our understanding of molecular chaperone function in membrane protein biogenesis lags far behind that in soluble protein biogenesis. Through a combined approach including isothermal titration calorimetry, UV-Vis spectroscopy, and fluorescence spectroscopy, the behavior of ATP-dependent chaperonin GroEL-GroES, a paradigmatic chaperone of soluble protein folding, was investigated in the refolding of membrane protein bacteriorhodopsin (BR) and its membrane insertion. We found that BR bound asymmetrically to the double-ring GroEL, w让h a much higher affinity when it was partially denatured. GroEL alone showed a clear influence on BR refolding, but the presence of ATP was necessary to significantly enhance both the rate and yield of the GroEL-mediated folding, in contrast to the adverse effect of GroES on the folding yield. However;synergy between ATP and GroES was shown to be required not only for releasing high-affinity BR species from GroEL, but also for unfolding and rescuing the misfolded conformers complexed to GroEL. This is consistent with the observation that maximum rate enhancement of BR refolding or assembly with the prepared inverted membrane vesicles was achieved when the complete chaperonin system was used. Our results support the iterative unfolding mechanism of GroEL activity previously proposed for soluble proteins, whereby GroEL might perform repeated unfolding and release of BR, thus offering additional opportunities for timely folding or membrane integration. This work provides important information on the convergence of folding of membrane and soluble proteins in light of folding pathways and the role of molecular chaperones. 展开更多
关键词 CHAPERONIN MEMBRANE PROTEIN MEMBRANE reconstitution PROTEIN FOLDING PROTEIN structure
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